const headerHeight = header.offsetHeight;
let lastScroll = 0;
window.addEventListener('scroll', function() {
const currentScroll = window.pageYOffset;
if (currentScroll > headerHeight) {
banner.classList.add('fixed');
document.body.style.paddingTop = banner.offsetHeight + 'px';
// Плавное скрытие/показ при скролле вниз/вверх
if (currentScroll > lastScroll) {
banner.style.transform = 'translateY(-100%)';
} else {
banner.style.transform = 'translateY(0)';
}
} else {
banner.classList.remove('fixed');
document.body.style.paddingTop = '0';
banner.style.transform = 'translateY(0)';
}
lastScroll = currentScroll;
});
});